Codeforces_96A

//Codeforces Round 96A
#include <iostream>
using namespace std;
int main()
{
    char n;
    int sum_od=0, sum_nl=0, answ=0;
    while(cin >> n)
    {
        if(n=='1'){sum_od++;sum_nl=0;}
        else{sum_nl++;sum_od=0;}
        if(sum_od==7 || sum_nl==7){answ=1;}
    }
    if(answ==0){cout<<"NO";}
    else{cout<<"YES";}
    return 0;
}